Cushioned bearing assembly



Dec. 12, 1967 E, M|L| ER GUSHIONED BEARING ASSEMBLY Original Filed Jan.4, 1962 INVENTOR Harvey E. Miller ATTORNEYS Patented Dec. 12, 19673,357,758 CUSHIONED BEARING ASSEMBLY Harvey E. Miller, Logansport, Ind.,assignor to The General Tire & Rubber Company, Akron, Ohio, acorporation of Ohio Original application Jan. 4,1962,.Ser. No.164,361,now

Patent No. 3,188,152, dated June 8, 19.65. Divided and.

this application Apr. 27, 1965, Ser. No. 451,125

2 Claims. (Cl. 30826) ABSTRACT OF THE DISCLOSURE This invention relatesto a mounting, bearing or sealing assembly having a tubular rubberinsert (9) compressed between concentric rigid metal sleeves (8 and 11)and having a sleeve member interposed between the insert and one of saidsleeves. Such sleeve member has many circumferential ribs and grooves(12 and 13) interfitting with similar ribs and grooves of the adjacentmetal sleeve to provide a seal and to restrain axial movement.

This application is a division of my copending United States patentapplication, Ser. No. 164,361, filed Jan. 4, 1962, now Patent No.3,188,152.

The present invention provides a bearing assembly suitable for use invarious types of pivotal connections between members having relativelyoscillating movements or as a support for a rotating member thatincludes a tubular elastic rubber cushioning element and that isdesigned to protect the rubber cushioning element against torsionalstresses which would tend to cause circumferential slip between therubber and the sleeves between which it is confinedaThe rubber insert ispreferably held under radial compression between the inner and outerrigid sleeves, one of which has a cylindrical part formed of a lowfriction material. The low friction material is preferably a resilientplastic material such as nylon, polytetrafluoroethylene such as soldunder the trade name Teflon or a linear acetal consisting of unbridgedpolyoxymethylene chains of great length such as sold under the tradename Delrin.

One of the coaxial sleeves between which the rubber insert is retainedin the assembly of the present invention is a two part sleeve composedof two relatively rotatable cylindrical parts, one fitting within theother for relative turning movements, the two part sleeve being soconstructed that it can be quickly and easily assembled with the rub-berinsert and the coaxial rigid sleeve.

Reference should be had to the accompanying drawings forming part ofthis specification, in which:

FIGURE 1 is a fragmentary top elevational view partially in section,showing an assembly embodying the invention, applied to the pivots of aCaterpillar tractor tread;

FIGURE 2 is a fragmentary side elevational view of the tractor treadshown in FIGURE 1;

FIGURE 3 is an end elevation of the bearing assembly employed in thetread hinges with a portion broken away and shown in section; and

FIGURE 4 is a section taken on the line 44 of FIG- URE 3, a portion ofthe inner cylindrical part of the two part bearing sleeve being brokenaway to show the split in the outer cylindrical part thereof.

In FIGURES 1 through 4 of the drawings, a bearing assembly embodying theinvention is shown applied to the hinges connecting the treads of aCaterpillar tactor. These hinges permit relative angular movements ofthe tread sections as they pass over the tread supporting wheels and thebearing of the present invention serves as a seal to prevent escape oflubricant from the ends of the hinge pin bearings and to prevent entryof moisture and dirt into the bearing.

As shown in FIGURE 1, the Caterpillar tread sections 1 are attached bymeans ofbolts 2 to chain links 3 which are provided with integralbearing sleeves 4 extending lengthwise of. one edge of each treadsection and with hearing caps 5 that project past the opposite edge ofeach tread section and receive the bearing portions .4 of the adjacentlink between them.:Each of the hinged joints has a pivot pin 6 extendingthroughout the length of the bearing portion 4 and projecting past theends of the bearing portion into the caps 5. Each bearing portion 4 hasa counterbore 7 at each end thereof which receives a bearing assemblywhich 'has an outer circumferentially continuous rigid: sleeve '8 whichmay be formed of metal and have a press fit within the counterbore 7.Within the sleeve 8 there is an elastic rubber insert 9 which isretained under radial compression between the outer sleeve 8 and aninner two part bearing sleeve which has an outer cylindrical part 10which is composed of a resilient material having a low coefiicient offriction and an inner circumferentially continuous cylindrical part 11which may be formed of metal and which fits within the part10, the parts10 and 11 being relatively rotatable.

The outer part 10 is provided with circumferential grooves 12 whichprovide circumferential ribs 13 between them and the inner part 11 ofthe bearing sleeve has circumferential grooves 14 and ribs 15 whichinterfit with the ribs and grooves of the sleeve member 10. The outersleeve part 10 is preferably formed of a resilient plastic material thathas a low coefficient of friction and the bearing members 10 and 11 mayturn relatively to one another without subjecting the elastic rubberinsert 9 to substantial torsional stresses. The sleeve parts 10 and 11are assembled prior to their insertion into the elastic rubber insert 9,and, in order to permit assembly, the resilient plastic member 10 isprovided with a longitudinal split 16 which permits it to be expandedand slipped over the inner circumferentially continuous member 10 andcon tracted to bring its ribs 13 into engagement with the grooves 14 ofthe inner sleeve part. When so assembled, the inner bearing sleeve canbe forced into the rubber insert 8 while it is confined within the outersleeve -7 by conventional methods of assembly.

The inner sleeve part 11 may have a close fit on the pivot pin 6 so thatthe relative turning movement is between the plastic sleeve member 10and the inner circumferentially continuous sleeve member 11 and thebearing is provided with an effective seal against escape of lubricantand against entry of dirt and moisture into the space between the pin 6and the bearing sleeve 4.

The bearing assembly is designed to be capable of convenient assembly.by methods now in common use such as disclosed in the patent to Beck2,660,780, granted Dec. 1, 1953. The rubber insert 9 may be contractedand forced into the sleeve 8 by forcing it through a funnelshaped. guidewhich has its small delivery end registered with one end of the sleeve'8. After assembly of the insert with the sleeve 8, the inner two partbearing sleeve can be forced into the rubber insert 9 behind a suitably"tapered pilot or other expanding means which expands the opening of thetubular insert 9 to a diameter to receive the bearing sleeve.

It is to be understood that in accordance with the provisions of thepatent statutes, variations and modifications of the specific devicesherein shown and described may be made without departing from the spiritof the invention.

What I claim is:

1. A cushioned sealing assembly comprising a rigid inner metal sleeve(11) having an internal cylindrical surface and an external surface ofrevolution containing a series of narrow circumferential ribs andgrooves (14 and 15) spaced apart throughout the length of said sleeve, alongitudinally split resilient sleeve member (10) formed of a lowfriction plastic material and having an external cylindrical surface andan internal surface of revolution containing circumferential ribs andgrooves (12 and 13) interfitting with the ribs and grooves of said metalsleeve, a rigid circumferentially continuous outer metal sleeve (8)having an inner cylindrical surface concentric to said inner metalsleeve and said sleeve member, and a tubular insert (9) of elasticrubber retained under radial compression between said outer metal sleeveand said low-friction sleeve member.

2. A tractor tread assembly having a series of tread sections, eachsection having a link rigidly connected thereto, and hinge meanspivotally connecting each link to an adjacent link including a rigidouter bearing sleeve and a pivot pin fitting in said sleeve, a cushionedsealing assembly comprising an inner rigid sleeve mounted on said pivotpin, an outer rigid sleeve mounted in said bearing sleeve, a tubularinsert of elastic rubber retained under compression between saidsleeves, one of said sleeves being formed of metal, the other of saidsleeves comprising two cylindrical parts, one fitting within the otherand rotatable with respect to the other, the cylindrical part adjacentsaid tubular insert being composed of a resilient non-metallic lowfriction material and the other cylindrical part being composed of arigid metal, said cylindrical parts having interfitting endless circularcircumferential ribs and grooves spaced apart throughout the length ofsaid cylindrical parts to prevent escape of lubricant and entry ofmoisture and dirt and to restrain relative axial movement of saidcylindrical parts.

References Cited UNITED STATES PATENTS 2,827,303 3/ 1958 Herbenar.3,009,746 11/ 1961 Haushalter 30826 3,094,376 6/ 1963 Thomas. 3,107,95110/1963 Palm 308-238 3,194,614 7/1965 Thomas 308--26 MARTIN P.SCHWADRON, Primary Examiner.

FRANK SUSKO, Assistant Examiner.

1. A CUSHIONED SEALING ASSEMBLY COMPRISING A RIGID INNER METAL SLEEVE(11) HAVING AN INTERNAL CYLINDRICAL SURFACE AND AN EXTERTNAL SURFACE OFREVOLUTION CONTAINING A SERIES OF NARROW CIRCUMFERENTIAL RIBS ANDGROOVES (14 AND 15) SPACED APART THROUGHOUT THE LENGTH OF SAID SLEEVE, ALONGITUDINALLY SPLIT RESILIENT SLEEVE MEMBER (10) FORMED OF A LOWFRICTION PLASTIC MATERIAL AND HAVING AN EXTERNAL CYLINDRICAL SURFACE ANDAN INTERNAL SURFACE OF REVOLUTION CONTAINING CIRCUMFERENTIAL RIBS ANDGROOVES (12 AND 13) INTERFITTING WITH THE RIBS AND GROOVES OF SAID METALSLEEVE, A RIGID CIRCUMFERENTIALLY CONTINUOUS OUTER METAL SLEEVE (8)HAVING AN INNER CYLINDRICAL SURFACE CONCENTRIC TO SAID INNER METALSLEEVE AND SAID SLEEVE MEMBER, AND A TUBULAR INSERT (9) OF ELASTICRUBBER RETAINED UNDER RADIAL COMPRESSION BETWEEN SAID OUTER METAL SLEEVEAND SAID LOW-FRICTION SLEEVE MEMBER.